<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>

<h1>Tela de Login</h1>
        <form action="<c:url value="/login"/>" method="POST">
            <input type="text" name="login.usuario" />
            <input type="password" name="login.senha" />
            <input type="submit" name="btnSubmit" value="Logar" />
        </form><br />
        <div>
            <c:if test="${not empty erro}">
                ${erro}
            </c:if>
            <c:if test="${not empty validacao}">
                <c:if test="${validacao == false}">
                    Login e/ou senha incorretos!
                </c:if>
            </c:if>
        </div>